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Basie Left Channel Bad

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Hi All,
I finished my Basie, triple checked everything, and have a problem. The right channel works great, but I have no signal in the left channel. Instead I have a hum. The hum is lower in output than the right (good) channel.
All of my voltages check out perfectly. I also checked for a good ground by putting the negative of my voltmeter on star ground, positive on the IEC ground. Checks out perfectly.
I swapped tubes to check for a bad tube. I also swapped my interconnects. It's not my power amp.
Here's the strange thing. I checked for residual noise. Right channel measures 8.4 mV. I expected a far higher reading in the left (bad) channel. Instead, I measured 3.7 mV AC.
I rechecked again for shorts, opens, and bad solder joints. I reflowed a few solder joints that looked suspect. No difference.
I'm stumped, and a bit frustated. Any ideas?
Thanks,
Nels

Follow Ups:

Re: Basie Left Channel Bad - troporobo 21:44:14 02/02/06 (1)
Sounds weird, but plausible if you have a cold solder joint somewhere that you haven't spotted. What a pain to reflow all of them though! I'm no expert and still in the process of building mine so can only offer a few questions:
* You checked voltages for the heaters on each socket B-E?
* Does the problem occur for all inputs?
* For both sets of outputs?
* Does it happen only on the phono stage or on any input?
* You swapped the correct tubes? (the line stage uses a separate tube for each channel in positions B and C but the MM stage shares left and right in each of the 12AX7 and 12AT7 tubes in positions D and E)
* Could it be either the volume pot or the selector switch?
* Last but not least, is it possible that a wire has some melted insultation from your soldering iron and is shorting (been there, done that!)
Apologies in advance if these are too basic. Please post your findings when its sorted out!
- Re: Basie Left Channel Bad - Nels Ferr� 22:35:29 02/02/06 (0)
  * You checked voltages for the heaters on each socket B-E?
  Yes. All voltages good. By the way, I only have sockets B-D, as my Basie is a line stage only. I bought a Cole to go with it.
  * Does the problem occur for all inputs?
  Yes
  * For both sets of outputs?
  Yes
  * Does it happen only on the phono stage or on any input?
  All inputs.
  * You swapped the correct tubes? (the line stage uses a separate tube for each channel in positions B and C but the MM stage shares left and right in each of the 12AX7 and 12AT7 tubes in positions D and E)
  The line stage only uses 12AT7's.
  
  * Could it be either the volume pot or the selector switch?
  I swapped out the volume pot from the PEC to an ALPS Blue. No difference.
  Thanks,
  Nels

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